I’d love to know more about how much baking soda can be neutralized by various acidic ingredients.

In the Cake Bible, Rose says 1 cup of buttermilk will react with 1/2 teaspoon of baking soda, to give as much rise as 2 1/4 teaspoons of baking powder. (It’s in the Understanding Cakes section under Leavening.)

This is great! But now I want to know more about other acidic ingredients. How much baking soda can you use with natural (un-Dutched) cocoa? With unsweetened baking chocolate? With molasses, honey, brown sugar….well, you get the picture.

And I recall somewhere on her blog Rose says that baking soda will also react with the natural acidity of flour. Anyone know more about that?

Barbara, In relation to your question about the use of baking soda & dutched cocoa powder…In this style of cocoa the acidity
has been removed…. hence we do not require baking soda to neutralize the acidity in this case.

Barbara, generally speaking, 1/4 teaspoon of soda is all that is required per 1 cup of flour. Remember that soda has 4X the leavening power of powder.
As far as the amount of acidity in flour, in general Barbara, there is very little there, you are not required to make any adjustment there because in the properties of baking powder, baking powder contains enough of soda to handle the slight acidity in the flour.
we must only concern ourselves with mostly acididic ingredients such as dairy products, fruits & their juices, choco, ete.
Barbara I hope this helps to answer your questions about baking science.

there are no hard and fast rules when it comes to baking soda and cocoa powder, an excess of alkalinity is what gives Devil’s food cake a reddish color. but way too much and it tastes like soap. When cocoa is not “dutched” it will have varying levels of acidity - to some point you can smell for this. For sweeteners you also have to consider the liquid component. If you want to get very specific, maybe you can look up the pH of various ingredients and look how much soda is used in the differend recipes. Also, cakes will tend to have less leavening and more liquid than biscuits and scone (quick breads), but more leavening and more liquid than cookies or pastry doughs.